Effect of particle size and co-extractant on Momordica charantia extract yield and diffusion coefficient using supercritical CO2

Supercritical carbon dioxide (SC-CO2) is a fluid with high diffusivity and low viscosity which can penetrate deep into the solid particle efficiently compared to liquid or gas. SC-CO2 commonly used as a green solvent in the modern extraction of bioactive compound from plants. Sometimes, a co-solvent was added in the system to increase solvent polarity or mix a co-extractant with dried sample to improve solute’s transport properties. Hence, the aim of this study was to determine Momordica charantia extract yield with different mean particle size as well as diffusion coefficient, De in the extraction process with and without co-extractant. Different mean particle sizes used were 0.2, 0.3, 0.5 and 0.7 mm at constant operating condition (20 MPa, 65 oC and 4 mL/min). A ratio 1:3 of pure ethanol was used in the extraction process with co-extractant. Based on the results, mean particle size of 0.3 mm gave the highest extract yield, 3.32% and 1.34% with and without co-extractant respectively. Whereas, the value of De at 0.3 mm mean particle size, with and without co-extractant are 8.820 x 10-12 and 7.920 x 10-12 m2/s respectively. Therefore, 0.3 mm is the best mean particle size to produce highest Momordica charantia extract yield and De value in SC-CO2 extraction with co-extractant